Component Functional Description - EGR Cooler

The Exhaust Gas Recirculation (EGR) Coolers use engine coolant to reduce the temperature of the exhaust gas that is recirculated to reduce NOx emissions.

The high pressure EGR cooler has a bypass tube which allows the hot EGR exhaust gases to bypass the cooler when the EGR bypass valve is opened during cold ambient, cold start conditions. This allows the engine to warm up quickly. The bypass valve is controlled by the Powertrain Control Module (PCM). The EGR cooler bypass valve is supplied vacuum from the EGR cooler bypass vacuum solenoid located on the right side of the engine next to the cylinder head cover. When the PCM energizes the solenoid in the EGR bypass valve it allows the vacuum to pull on the diaphragm opening the bypass to divert the exhaust gases around the EGR cooler.

Courtesy of CHRYSLER GROUP, LLC

The low pressure EGR cooler does not have a bypass since the low pressure EGR is not operated when the engine is cold.